With the news filtering through from France that the incumbent Wales fly-half Stephen Jones had injured an ankle playing for Clermont- Auvergne, the national coach, Mike Ruddock, watched Robinson with interest.
The talented fly-half scored a try and kicked 17 points in a comfortable victory. His opposite number, Glen Jackson, kicked accurately, but his side had no answer to a team who are finally starting to deliver performances to match the quality of their personnel.
The opening stages of the match were barely noticed by the 8,000-strong crowd, however, as fans discussed the impending arrival of the All Black legend Jonah Lomu.
Lomu, who has scored 37 tries in his 63 Tests for New Zealand, says his seven-month stint with the Blues will set him up for a return to his beloved All Black No 11 jersey after a life-saving kidney transplant 15 months ago.
"I'm excited by the challenge," he said. "It's great that Cardiff want to help me achieve what I want to achieve. They have bent over backwards to get me there. This will be a huge help in terms of where I want to head with my rugby. Now all I have to do is perform.
"It's a really exciting time to be involved in Welsh rugby. I have always felt a great warmth from the Welsh."
Lomu arrives in mid-November and may make his debut in the Powergen Cup match at London Irish. The Welsh Rugby Union chief executive, David Moffett, said the news was "absolutely huge". He added: "Jonah is still the biggest icon in the rugby world and he can bring a massive amount to the game in Wales. I hope he is fully fit, because if he is, he will make an enormous impact. Hopefully he will do wonders on the field like we all know he is capable of."
Craig Morgan put in a claim for the other wing spot when the big man arrives by scoring a 14th-minute interception try. A spilled ball then gave the Blues lock Craig Quinnell the chance to gallop down the touchline, and an inside pass gave Nicky Robinson's elder brother, the centre Jamie, a score.
Jackson kicked three points, but quick hands from Nicky Robinson gave Rhys Williams the space to make a 50-metre break and give the flanker Robin Sowden-Taylor a try.
Kevin Sorrell grabbed a try for Saracens before the break and their hooker Matt Cairns scored when Quinnell was in the sin-bin, but then Sorrell was yellow-carded for aprofessional foul.
Nicky Robinson then extended the Blues' lead with a penalty before converting his own try after some good work from the scrum-half Mike Phillips.
Cardiff Blues: R Williams (capt); C Czekaj, J Robinson (R Powell, 67), L Thomas (M Nuthall, 47), C Morgan; N Robinson, M Phillips; J Yapp, D Goodfield (R Johnson, 71), B Evans (M Jones, 54), C Quinnell (D Jones, 63), R Sidoli, M Molitika (X Rush, 52), A Powell, R Sowden-Taylor (M Williams, 63).
Saracens: N Obi (B Russell, 69); D Scarbrough, K Sorrell (A Powell, 70), D Harris, P Bailey; G Jackson, M Rauluni (A Dickens, 49); N Lloyd (K Yates, 49), M Cairns (S Byrne, 61), B Broster (N Lloyd, 75), S Raiwalui (K Chesney, 49), I Fullarton, T Randell, H Vyvyan (capt), D Seymour (B Skirving, 29-40; 54).
Referee: P Fear (Wales).Reuse content